Fix Google Mobile-Friendly Test issue in Prestashop 1.7

Prestashop 1.7 has issues with blocking CSS and JS cache files from theme folder by robots.txt. This cause that Google doesn't see the shop as responsive (it's not rendered correctly). To fix it, add these lines to your robots.txt (change theme folder name according to your theme).

Allow: */themes/yourtheme/assets/cache/*.css Allow: */themes/yourtheme/assets/cache/*.js